https://www.eia.gov/energyexplained/biomass/
Biomass is renewable organic material that comes from plants and animals. Biomass contains stored chemical energy from the sun that is produced by plants through photosynthesis. Biomass can be burned directly for heat or converted to liquid and gaseous fuels through various processes
Biomass was the largest source of total annual U.S. energy consumption until the mid-1800s. In 2022, biomass accounted for nearly 5% of U.S. total primary energy consumption. Biomass is used for heating and electricity generation and as a transportation fuel. Biomass is an important fuel in many countries, especially for cooking and heating in developing countries.
Biomass sources for energy include:
Biomass is converted to energy through various processes, including:
Direct combustion is the most common method for converting biomass to useful energy. All biomass can be burned directly for heating buildings and water, for providing industrial process heat, and for generating electricity in steam turbines.
Thermochemical conversion of biomass includes pyrolysis and gasification. Both processes are thermal decomposition processes wherein biomass feedstock materials are heated in closed, pressurized vessels called gassifiers at high temperatures. The processes mainly differ in the temperatures and in the amount of oxygen present during conversion.
A chemical conversion process known as transesterification is used for converting vegetable oils, animal fats, and greases into fatty acid methyl esters (FAME) to produce biodiesel.
Biological conversion of biomass includes fermentation to make ethanol and anaerobic digestion to produce biogas. Ethanol is used as a vehicle fuel. Biogas, also called biomethane or renewable natural gas, is produced in anaerobic digesters at sewage treatment plants and at dairy and livestock operations. It also forms in and may be captured from solid waste landfills. Properly treated renewable natural gas has the same uses as fossil fuel natural gas.
Researchers are working on ways to improve these methods and to develop other ways to convert and use more biomass for energy.
In 2022, biomass accounted for 5% of U.S. energy consumption, or about 4,930 trillion British thermal units (TBtu). The types, amounts, and the percentage shares of total biomass energy consumption in 2022 were:
The amounts—in TBtu—and percentage shares of total U.S. biomass energy use by consuming sector in 2022 were:
The industrial sector accounted for the most, in terms of energy content and percentage share, of total annual U.S. biomass consumption in 2022. The wood products and paper industries use biomass in combined heat and power plants for process heat and to generate electricity for their own use.
The transportation sector accounted for the second-highest amount and percentage share of biomass (as biofuels) consumption in 2022.
The residential and commercial sectors use firewood and wood pellets for heating. The commercial sector also consumes, and in some cases, sells renewable natural gas produced at municipal sewage treatment facilities and at waste landfills.
The electric power sector uses wood and biomass-derived wastes to generate electricity for sale to the other sectors.
On an energy content basis, U.S. total biomass energy exports exceeded total biomass energy imports in 2022.
Densified biomass fuels (wood pellets and other densified biomass fuels) have become a U.S. export commodity in recent years. In 2022, the United States exported about 8.8 million tons of wood fuel pellets (Table 8).
Last updated: June 30, 2023, with data from the Monthly Energy Review, April 2023; data for 2022 are preliminary.